Tank Access Plate System, 21" Stainless Steel

If you have contamination problems with your diesel or water tanks, or simply wish to provide access for future maintanance, the SeaBuilt Access Plate System is the perfect answer.
This ingenious (patented) Access Plate System is easy to install but also ensures that the structural integrity of the tank is maintained without leaks.

The SeaBuilt Access Plate System is available in aluminum or stainless steel - each in 5 sizes (6" to 21").

• Features internal and external gaskets against the tank surfaces - so the plate is isolated from the tank
• Installs without the use of any messy gasket compound - the gaskets make the seal
• Upper gasket secures the backing ring up against the back surface of the tank, preventing it from falling into the tank
• Compatible with aluminum, stainless steel, Monel, steel, iron, fiberglass and polyethylene tanks
• Note that the actual hole in the tank is 2" smaller than the access plate size - so the 6" size is just large enough for most hands to pass through
• NOT for use on gasoline tanks

Aluminum Access Plates are only recommended for use on diesel fuel tanks. The tanks can be made of any material except Monel or stainless steel.

Stainless Steel Access Plates are recommended for use on Monel and stainless steel diesel fuel tanks.
Additionally, Stainless Steel Access Plates should be used on all water and holding tank materials (some exceptions apply).


Installation basics...
This device consists of a flat round plate with stud holes drilled in it, and a folding ring plate with studs attached. Also included are two gasket rings with holes for the studs.
After the access and stud holes are drilled in the tank, and the opening is prepped, one of the gasket rings is fitted over the studs on the folding ring.
The folding ring is insrted through the access hole in the tank, opened up, and the studs are then inserted through their holes from the back side.
While being held in place, the second gasket ring is pressed over the studs on the outside of the tank.
This second gasket will hold the backing ring up against the back surface of the tank, preventing it from falling into the tank.
The flat deck plate/cover is then placed over the studs and secured with nuts and lock washers — sandwiching the gaskets against the tank surfaces - completely sealing the opening from any leaks.
The top plate can be removed at any time to access the inside of the tank.

Click here to view the Access Plate Installation Instructions.
Note — When reading the "Official" Installation Instructions, you may find it useful to refer to the above description for clarity.